Mechanical headlamp adjusting means

ABSTRACT

Mechanical arrangements for automatically raising or lowering of light beams emitted by vehicle headlamps responsive to uneven sag of the vehicle body at the front and at the rear, the arrangements providing flexible connections extending between parts associated with and movable relative to sprung and unsprung vehicle members and adapted to control the operation of a light beam adjusting mechanism in or against a direction of applied resilient biassing. The flexible connections being of a kind for leading along tortuous paths as may be required on different vehicles.

United States Patent Yssel [54] MECHANICAL HE'ADLAMP ADJUSTING MEANS [72] inventor: Gideon Petrus Schoeman Yssel, P. O. Noordburg, Potchefstroom, T ined. p i s of So E Q 22 Filed: May 26, 1970 211' App]. No.: 40,605

[30] r Foreign Application Priority Data May 29, 1969 South Africa ..69/3851 [52] US. Cl. ..240/7.1, 240/612, 240/6l.5, 240/623 [51] Int. Cl. ..B60q l/00 [58] Field of Search ..240/62.6, 62, 62.5, 63, 61.2, 240/6l.8, 61.4, 61.5, 7.1, 7.1 L]

[56] References Cited UNITED STATES PATENTS I 1,817,256 8/1931 Heikens ..240/62.3

[451 Oct. 10, 1972 2,049,802 8/1936 Hamm ..240/62.3 2,105,866 l/l938 Sheaffer ..240/7.1 2,250,734 7/ 1941 Thompson et al ..240/62.3 3,316,397 4/1967 Yssel ..240/7.l LJ 3,370,162 2/ 1968 Biabaud ..240/7.1 LJ

Primary Examiner-Louis J. Capozi Attorney-Karl W. Flocks [57] ABSTRACT Mechanical arrangements for automatically raising or lowering of light beams emitted by vehicle headlamps I responsive to uneven sag of the vehicle body at the front and at the rear, the arrangements providing flexible connections extending between parts associated with and movable relative to sprung and unsprung vehicle members and adapted to control the operation of a light beam adjusting mechanism in or against a direction of applied resilient biassing. The flexible connections being of a kind for leading along tortuous paths as may be required on different vehicles.

10 Claims, 14 Drawing Figures PAIENTEDUBT 10 m2 3.697.741

SHEET 1 [IF 3 MECHANICAL HEADLAMP ADJUSTING MEANS BACKGROUND OF THE INVENTION FIELD OF THE INVENTION THIS INVENTION relates to improved means for automatically adjusting the headlamps of a motor and like vehicle having the headlamps mounted on a body which is resiliently carried on the wheels so that during darkness the light beams remain correctly directed with respect to a mean plane containing the wheel axes under varying difierently loaded conditions of the vehicle body or when rapid acceleration or deceleration takes place. When the load on a vehicle body is disposed at different locations or positions, or when the vehicle is rapidly accelerated or braked, the rear and/or the front (as the case may be) of the vehicle sags which has the undesirable and often dangerous effect of changing the mean angle of the light beams, emitted by the headlamps, relative to the road surface.

DESCRIPTION OF PRIOR ART In the specification of my prior US. Pat. No. 3,316,397 various forms of automatic vehicle headlamps adjusting means are disclosed. In a number of these forms a fluid is employed to transmit motion for adjustment of tiltably mounted headlamps. Mechanically operated means are also disclosed inthe specification of this prior patent. This invention provides simplified, inexpensive and more reliable mechanically operated arrangements for responsive light beam changing and which are readily applicable on new or existing vehicles having different kinds of suspension mechanisms.

SUMMARY OF THE INVENTION According to the invention a mechanical actuating arrangement for automatic adjustment of a light beam emitted by at least one headlamp of a vehicle having a resiliently suspended body and mechanical parts at the front and rear which are movable relative to the body and a mean plane containing the axes of the wheels on movement of the body relative to said plane, and also having at least one headlamp attached to a mechanism whereby the mean angle of the emitted light beam is changed relative to the body for controlling the said angle in proportion to a resultant difference in displacement of the front and rear of the vehicle body, which includes an elongated flexible member attached to a relatively movable part at one end of the vehicle and to the mechanismadapted to change the angle of the light beam emitted by the headlamp, and a connection from the relatively movable part at the opposite end of the vehicle to the said light beam angle changing mechanism; the connections of the relatively movable vehicle parts to the light beam angle changing mechanism being such that different displacing movements of the relatively movable parts at the opposite ends of the vehicle, in the same or in opposite directions, are applied to the said light beam angle changing mechanism and adapted to provide a resultant angular changing of the headlamp light beam in proportion and relative to vertical displacements of the body at the front and the rear of the vehicle.

The elongated member comprises a flexible cable capable of being led and guided along a tortuous path from the relatively movable part at one end of the vehicle to the light beam angle changing mechanism. In the connections between the relatively movable vehicle parts and the mechanical light beam angle changing mechanism spring-like devices may be provided to present a lost motion efl'ect for avoid instantaneous changes of the light beam angles so that flickering, due to road surface irregularities, may be prevented.

The light beam angle changing mechanism may comprise a switch device controlling energizing of any one of a number of lamp filaments provided in the headlamp. Such switch device should include an operating arm to which the actuating arrangement is connected. Such is preferably spring loaded and against which the said arrangement is adapted to act. The switch device is adapted to be advanced to connect different filaments separately to the electric current supply source for changing the angle of the emitted light beam in relation to the vehicle body and the plane contained in the axes of the wheels.

In another form of the invention the headlamp is or the headlamps are tiltable in forward and rearward directions. Alternatively at least the reflector/s of the headlamp/s is/are pivotally mounted about a transverse axis.

The flexible elongated member, accordingto one form of the invention is a cable of the sheathed kind, of which a core cable is axially displaceable therein. In other forms cables or wires are used.

Reference will now be made to the accompanying drawings which illustrate a number of forms of the invention. A better understanding of the invention will be obtained from the drawings, while further features of the invention will be apparent from the description with reference to the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS.

In the drawings:

FIGS. 1, 2, 3, 4, 5, 6, 7, 8 and 9 are diagrammatic views showing nine modified forms of the mechanical arrangement and means for automatic adjustment of light beams emitted by headlamps of a vehicle constructed according to the invention;

FIG. 10 is a diagrammatic view showing a modified form of connection of the mechanical arrangement to semi-eliptical rear springs of a vehicle;

FIG. 11 is a view of a part incorporated in the form of the arrangement shown in FIG. 4;

FIG. 12 is a modified form of the part shown in FIG. 11;

FIG. 13 is a further modified form of the part shown in FIG. 11; and

FIG. 14 is a still further modified form of the part shown in FIG. 1 1.

PREFERRED FORM OF THE EMBODIMENTS In FIG. 1 numeral 10 denotes an anti-roll bar which is at the rear of the vehicle and having a downwardly directed central crank arm 12. An anti-roll bar at the front of the vehicle is denoted by numeral 14 and is also provided with a downwardly directed crank arm 16 at its middle portion. On the vehicle a pair of headlamps 18, or only the reflectors of the headlamps, are tiltably mounted about transverse horizontal axes. The headlamps 18 or their reflectors are preferably biassed by a spring 20 adapted to apply an upwardly tilting bias to the headlamp or the reflectors.

The headlamps 18 are caused to be tilted downwardly by links 22 connected onto crank arms 24 provided on a joumalled shaft 26. The shaft 26 in turn is provided with an actuating crank arm 28. The crank am 28 is connected by a cable 30 to the crank arm 12 of the rear anti-roll bar after passing through thecrank arm 16 of the front anti-roll bar 14. A portion of the cable 30 slidably engages a sheath 31. The sheath 31 is fixed by one end to the front of the crank arm 16 of the front anti-rollbar l4 and has its opposite end fixed to the chassis or body of the vehicle as at 32. The front end of the cable 30 is attached to the actuating crank arm 28.

When the rear of the vehicle body sags, the cable 30 is pulled rearward and the shaft 26 and crank arms 24, 28 are caused to rotate forwardly through a small angle and causes the headlamps 18 to tilt downwardly adjacent the action of spring 20. Such downward tilting is in proportion to the extent of the sag of the rear of the vehicle body. The angle of downward dip of the headlamps is such that the road ahead remains illuminated at a constant distance forwardly of the vehicle. When the front of the vehicle also sags the rear end of the sheath 31 is forced rearwardly by crank arm 16 due of the front anti-roll bar 14, and with wide clearance through the elongated actuating crank arm 28.1. The front end of cable 30.1 is provided with an adjustable 1 head 34. Over the cable 30.1 compression springs 36 are provided bearingly engaging respectively opposite sides of the actuating lever 28.1 and the crank arm 16.1

and head 34.

FIG. 3 shows an arrangement, of the kind shown in FIG. 2, where it is impractical to have crank arm 16.1 and also crank arm 12 extending upwardly. The cable 30.1 is connected to one limb of a bell-crank lever 40 which is pivotally suspended from the vehicle body as downward tilting of the headlamps. In this-form the 7 links 22 are connected to the bottom of the head-lamps and not the top as is shown in FIG. 2. The crank arm 16 of the front anti-roll bar is directed downwardly.

FIG. 4 shows a form of the invention suitable for application on vehicles which are not provided with antiroll bars or where it is not practical to employ anti-roll bars with crank arms. In this form a bell crank lever 40 is provided which is attached to the vehicle body is swivelable and preferably biassed fashion to maintain contact with the axle casing 44. Arm 42.1 of the lever 40 is bearingly held in engagement with a center portion of the rear axle casing 44, e.g. the differential casing, while the arm 42 is connected by cable 30.2 to the actuating crank arm 28 of the shaft 26. A portion of the cable 30.2 passes over a pulley 46 mounted on a transverse bar 48 which in turn has oneend pivotally, and the opposite end pivotally and slidably, connected to transverse and swingably mounted spring carrying and wheel mounting beams, wishbone frames or brackets 50 of the vehicle. When the front of the vehicle sags the pulley 42 moves upwardly relative to the body, permitting upward tilting of the headlamps 18 due to the biassing by spring 20. On sagging of the rear I of the vehicle the cable 30.2 is drawn rearwardly and causes downward tilting of the headlamps 18. On sagging of both the front and rear ends of the vehicle the said up ward movement of pulley 46 may neutralize, reduce or exceed the extent of downward pivoting pull applied to the crank arm 28 from the rear of the vehicle. The bellcrank lever 40 may be fixed to the body in suspended fashion by a resilient material block 52 (see FIG. 1 1).

The form of the invention shown in FIG. 5, particularly suitable on motor vehicles of which 'the differential gear casing 54 is suspended from the body and from which swivelable rear axles 56 extend, provides for the rear end of the cable 30.2 to be fixed to a rigid transverse bar. 58 which has its ends swivelably attached to downwardly projecting arm forming brackets 60 fixed on'rear axle bearing locating ties 62 which in turn are pivotally attached to the vehicle body. At the front of the vehicle a pulley 46 is provided rotatably on a transverse pin extending from the free end of crank arm 16.2 fixed to and projecting rearwardly from the middle portion of a front anti-roll bar 14. The pulley .46 moves upwardly relative to the body on sagging of the front end of the vehicle. On sagging of the rear end of the vehicle the arms of the brackets 60 move rearwardly to produce the required pull in cable 30.2 for downward tilting of the headlamps. FIG. 10 shows a modification with the cable 30.2 fixed to the center of a light bar 66 whereas cables 30.6 connect the outerends of bar 66 to the downwardly directed arms of brackets 60 fixed to ties 62 or semi-eliptical springs. The arm forming brackets should be mounted close to the front swivelable ends of the ties 62 or the said springs. semieliptical I FIG. 6 shows a modification in which the rear end of cable 30.2 is attached to the vehicle body 32 at the rear of the latter and arranged to pass over a pulley 46.1 which is joumalled on a transverse bar 58.1. Bar 58.1 is swivelably attached by the ends to the rear axle bearing locating ties 62 or rear semi-elliptical springs so that on sagging of the vehicle at the rear the pulley 46.1 moves towards the body. At the front the arrangement according to FIG. 3 or according to any of those shown in 4 or 5, when modified, may be used. As the drive shaft to the differential 54 may obstruct central location of the pulley 46.1 on the bar 58.1, such pulley may be disposed at a'slightly off-center position on the bar. The attachment of the bar 58.1 onto the members 62 are closer to the pivot axis of such members a the one side of the vehicle than to the other. Consequently the proportion of the distances of the pulley 46.1 to the ends of the bar 58.1 should be in the same proportion as the spacing of the ends of the bar from the pivot axis of the members. Thus the proportion of alb= d/c In the form of the invention according to FIG. 7 one end of the cable 30.3 is attached to the rear anti-roll bar crank arm 12 and the other end to one end of the horizontally suspended light rigid bar 66.1. The opposite end of the bar 66.1 is connected by cable 30.4 to crank arm 28.-1. Cable 30.5 connects the front anti-roll bar crank arm 16, which differs in length from arm 12, to bar 66.1 at a position determined by a proportion of u/v y/x Cables 30.3 and 30.5 are kept under tension by spring 68, attached to the body 32, while the headlamps 18 are biassed by spring 20 to a downward] sloping position.

FIG. 8 shows an arrangement where the crank arms 12, 16 on the anti-roll bars 10, 14, differ in length and move in the same direction with opposite movement of the front and the rear ends of the vehicle body (-i.e. when the front lifts and the rear sags). The cables 30.3 and 30.5 must be attached to the ends of bar 66.2 with cable 30.4 connected to bar 60 spaced to and between them in such a position that bar 66.2 is divided in proportion to the lengths of the crank arms 12 and 16 according to e/f= g/h FIG. 9 illustrates an application of the invention on a vehicle of which the rear wheels are mounted on levers 80 which are pivotally attached to the vehicle body. On the joumalled stub shafts of said levers 80 crank arms 82 are provided which are attached to cable 30.2 by convergingly arranged cables 30.6.

The connection of such cables is preferable onto a ring 84. At the front, when a anti-roll bar is provided, the arrangement is substantially similar to that shown in FIG. 7. 1

On vehicles provided with an A bracket to assist location of the rear axle, the end of the cable or core cable may be attached to a center portion of the said A- bracket, onto a downwardly projecting arm on said bracket, or a cable pulley may be attached to said bracket.

The suspended mounting of bell-crank lever 40 by means of a resilient rubber or like material block part 52 provides a bias for the lever arm 42.1 to be maintained in pressing engagement onto the axle casing 44. The form of lever 40.1 shown in FIG. 12, and for the same purpose as bell-crank lever 40, comprises a curved blade spring adapted for bolting, rivetting or like fixing to the body by end 70 while the opposite end region bearingly and slidably engages on the axle casing 44. Between the ends of the lever 40.1 a pin 72 extends downwardly and forms a lever arm for connecting thereto of cable 30, 30.1, 30.2. The lever 40.2, shown in FIG. 13, also comprises a curved blade spring of greater curvation than that shown in FIG. 12. End 70 is also fixed to the body 32 while a projecting pin 78 on an intermediate portion is adapted to slidingly bear on the axle casing 44 whereas the end portion 76 provides for the connection of the cable. In FIG. 14 a lever for the same purpose is shown. The said lever 40.3 is not resiliently biassed into engagement with the axle casing 44 but is pivotally suspended from body 32 and provides a bifurcated free end 74 which slidably embraces a part of the axle casing. Movement of the axle casing 44 towards or away from the body causes tilting of the lever 40.3. Lever 40.3 is also of bell-crank construction. The second arm 42.2 provides connection for the cable.

The variousand different forms of arrangements of parts, at the front and rear, according to the invention, may be applied in combination.

The arrangements shown and described provide mechanical means to automatically maintain light beams from headlamps at a constant distance in front of a motor vehicle as applicable on vehicles having different formsof body suspensions.

Should headlamps be used for the same purpose having diiferently positioned filaments, or should a number of differently mounted fixed headlamps be provided, a switch, having a control .arm, can be employed. Said control arm would be operated by a crank arm 28, 28.1 or 24 to control the electrical circuit to the required filament or headlamp.

On vehicles equipped with four double filament headlamps, one pair'is adjusted with no or a medium load on the vehicle and the other pair adjusted when laden. The switch terminates theelectric current to the dipped beams, adjusted when empty, and connecting or maintaining connection to the dipped filaments of the lamps adjusted when the vehicle is laden, whenever that pair of dipped beams approach the horizontal or are directed upwardly due to loading or acceleration, in order to eliminate dangerous dazzle.

The various cables maybe lead over pulleys, through eyes or the like along a tortuous or winding path where it is not possible or not desirable toextend straight to the connection points.

The arrangements may be applied to new vehicles and can alsobe readily fitted to existing vehicles. 14

lclaim: g

1. Mechanical means for automatically adjusting headlamps pivotally mounted on a. resiliently suspended body of a vehicle having wheels at the front end and at the rear end for maintaining asubstantially constant angle between light beams emitted by the headlamps and a mean plane containing the axes of the front and the rear wheels of the vehicle on uneven sagging of the front and rear ends of the body relative to said plane comprising: a joumalledoscillatable shaft transversely across the body and having crankarms connected by links to the headlamps, to a spring providing a bias to tilt the headlamps in one direction, and an actuator: a first member at the rear of the vehicle attached to the body and mountings for the rear wheels and adapted for movement in proportion to vertical movement of the body relative to the wheels: a second member at the front of the vehicle attached to the body and mountings for the front wheels to perform movement in proportion to vertical movement of the body relative to the front wheels; the actuator including a flexible cable fixed by one end to the said first member and by an opposite end to a crankarrn of the oscillatable shaft to effect downward tilting of the headlamps against the bias on sagging of and in proportion to downward movement of the rear of the body; a connection between the second member and the actuator to permit upward tilting of the headlamps on sagging of and in proportion to the downward movement of the front of the body; whereby responsive tilting movement of the headlamps is proportionately to uneven vertical displacement of the front and rear ends of the body relative to said plane.

2. Mechanical means for automatically adjusting headlamps of a wheeled vehicle, according to claim 1 including first and second members comprising antiroll bars having crankarms on their center portions, the crankarm of the first member being connected by a flexible cable to a movable headdisposed forward "of the crankarm of the second member and also forwardly of a crankarm of the oscillatable shaft which is disposed in spaced relationshipforwardly of the crankarm of the second member, a compression spring bearing on the crankarm of the second member and a rear side of the crankarm of the oscillatable shaft, a compression spring bearing on the-head and a front side of the crankarm of the oscillatable shaft,'whereby downward tilting of the headlamps is effected byrearward movement of the head and pressure application on the crankarm of the oscillatable shaft through the compression spring forwardly of said crankarm whereas a variable pressure in the opposite direction on said crankarm is provided by the compression spring between the rear face of said crankarmand the crankarm of the second member.

3. Mechanical means for automatically adjusting headlamps of a wheeled vehicle according to claim 1 including a first member comprising a bellcrank lever suspended movably from the body and of which one arm engages a rear wheel axle and differential casing of the vehicle and another arm providing connection for one end of the cable whereas the second member comprises an anti-roll bar having a crankarm on a center portion, a movable head on the opposite end of the cable disposed in spaced relationship forwardly of a crankarm of the oscillatable shaft and the crankarm of the anti-roll bar which is disposed 'rearvvardly of the crankarm of the'oscillatable shaft, compression springs bearing on front and rear sides of the crankarm of the oscillatable shaft and the head and crankarm of the anti-roll bar.

4. Mechanical means for automatically adjusting headlamps pivotally mounted on v a resiliently suspended body of a vehicle having wheels at front and rear ends for maintaining a substantially constant angle between light beams emmited by the headlamps and a mean plane containing the axes of the front and rear wheels of the vehicle on uneven sagging of the front and rear ends of the body relative to said plane, including; a joumalled oscillatable shaft transversely across I the body and having crankarms connected by links to the headlamps, to a spring providing a bias to tilt the headlamps in one direction, and to an actuating cable; a lever suspended from the body and having an arm portion engaging a central portion of a rear wheel axle and differential gear casing and another arm providing a connection for a flexible cable; a transverse bar connected by one end pivotally and by an opposite end pivotally and slidably to spring support and wheel mounting pivoted beams of the vehiclej a cable pulley joumalled on the center portion of the bar; a flexible actuating cable connected by one end to said lever and by the opposite end to a crankarm of the oscillatable shafts whereas an intermediate portion is passed around the pulley whereby sagging of the rear end of the body cause downward tilting of the headlamps against the biasing action of the spring while sagging of the front of the body cause raising of the pulley and tilting of the headlamps in the opposite direction by the 1' 8 spring, the movement of the pulley being adapted to counteract the action of the lever for tilting movement of the headlamps proportionately to the vertical movements of the rear and the front ,ends of the body relative tosaidplane. Y i

5. Mechanical means for automatically adjusting headlamps pivotally mounted on a resiliently suspended body ofa 'vehicle having wheels at a front end and at a rear end for maintaining a substantially constant angle between light beams emitted by the headlamps and a mean plane containing the axes 'of the front and the rear wheels of the vehicle on uneven sagging of the front and rear ends of the body relative to said plane including a joumalled oscillatable shaft transversely across the body and having crankarms connected by links to the headlamps, to a spring providing a bias to tiltable headlamps in one direction, and to an actuating cable; a transverse bar swivelably attached to short downwardly directed levers on tying members extending pivotally from the vehicle body to bearing mountings of the rear wheels and a connection on a center portion of the bar for one end of an actuating cable; a transverse bar connected by, one end pivotally and by an opposite end pivotally and slidable to spring supporting and wheel mounting pivot beams of the vehicle, a pulley rotatable on a center portion of the bar and engaged by an intermediate portion of the cable which is connected to a crankarm of the oscillatable shaft whereby on sagging of the rear of the body of headlamps are tilted downwardly against the biasing action of the spring while sagging of the front of the body causes raising of the pulley for upward tilting of the headlamps, said raising of the pulley being adapted to counteract the action of the cable from the rear of the vehicle for tilting of the headlamps proportionately to the uneven vertical displacement of the front and rear ends of the body relative to said plane.

6. Mechanical means for automatically adjusting headlamps of a vehicle according to claim 5 wherein the bar at the rear of. the vehicle is provided with a rotatable pulley substantially at a center portion thereof whereas the actuating cable has a rear end connected to the body of the vehicle and is passed over the pulley of the bar at the rear of the vehicle and over the pulley on the bar at the front of the vehicle for connection with an opposite end to a crankarm of the oscillatable shaft.

7. Mechanical means for automatically adjusting headlamps pivotally mounted on a resiliently suspended body of a vehicle having wheels at a front end and at a rear end for maintaining a substantially constant angle between light beams emittedby the headlampsand a mean plane containing the axes of the front and the rear wheels of the vehicle on uneven sagging and rear end of the body relative to said plane, including: a joumalled oscillatable shaft transversely across the body and having crankarms connected'by links to the headlamps to a spring providing a bias to tilt the headlamps in one direction, and to an actuating cato the front wheels; a lever having one end connected by a cable to a crankarm of the first member, an opposite end connected by a cable to a crankarm of the oscillatable shaft, a center portion connected by a cable to a crankarm of the second member, a portion between the connections of the first and second member connected to the body by a spring; whereby on uneven sagging of the rear and front ends of the body the end of the lever connected to the crankarm of oscillatable shaft is swung to an extend proportionately to the said uneven downward movement of the body causing similar proportional tilting movement of the headlamps relative to the plane.

8. Mechanical means for automatically adjusting headlamps as claimed in claim 7 wherein the front and rear members comprise anti-roll bars having on center portions crankarms which are attached by the cables to the levers at the said positions, the proportions of the lengths of the crankarms relative to the spaced positions of connection of the respective cables to the lever from the position of attachment of the lever to the crankarm of the oscillatable shaft being the same.

9. Mechanical means for automatically adjusting headlamps as claimed in claim 7 wherein the first member comprises a crankarm on each of two rear wheel mounting levers, pivotally connected to the body, whereas the cable provides a pair of diverging end portions of which the ends are each connected to one or said crankarms.

10. Mechanical means for automatically adjusting headlamps as claimed in claim 7 wherein a substantially transverse lever is provided having an intermediate portion connected to the crankarm of the oscillatable shaft and having opposite ends connected to crankarms of anti-roll bars by cables, the proportion of the lengths of the crankarms relative to the distance of attachment of the respective cables to the leverfrom the position of connection of the lever to the crankarm of the oscillatable shaft being the same. 

1. Mechanical means for automatically adjusting headlamps pivotally mounted on a resiliently suspended body of a vehicle having wheels at the front end and at the rear end for maintaining a substantially constant angle between light beams emitted by the headlamps and a mean plane containing the axes of the front and the rear wheels of the vehicle on uneven sagging of the front and rear ends of the body relative to said plane comprising: a journalled oscillatable shaft transversely across the body and having crankarms connected by links to the headlamps, to a spring providing a bias to tilt the headlamps in one direction, and an actuator: a first member at the rear of the vehicle attached to the body and mountings for the rear wheels and adapted for movement in proportion to vertical movement of the body relative to the wheels: a second member at the front of the vehicle attached to the body and mountings for the front wheels to perform movement in proportion to vertical movement of the body relative to the front wheels; the actuator including a flexible cable fixed by one end to the said first member and by an opposite end to a crankarm of the oscillatable shaft to effect downward tilting of the headlamps against the bias on sagging of and in proportion to downward movement of the rear of the body; a connection between the second member and the actuator to permit upward tilting of the headlamps on sagging of and in proportion to the downward movement of the front of the body; whereby responsive tilting movement of the headlamps is proportionately to uneven vertical displacement of the front and rear ends of the body relative to said plane.
 2. Mechanical means for automatically adjusting headlamps of a wheeled vehicle according to claim 1 including first and second members comprising anti-roll bars having crankarms on their center portions, the crankarm of the first member being connected by a flexible cable to a movable head disposed forward of the crankarm of the second member and also forwardly of a crankarm of the oscillatable shaft which is disposed in spaced relationship forwardly of the crankarm of the second member, a compression spring bearing on the crankarm of the second member and a rear side of the crankarm of the oscillatable shaft, a compression spring bearing on the head and a front side of the crankarm of the oscillatable shaft, whereby downward tilting of the headlamps is effected by rearward movement of the head and pressure application on the crankarm of the oscillatable shaft through the compression spring forwardly of said crankarm whereas a variable pressure in the opposite direction on said crankarm is provided by the compression spring between the rear face of said crankarm and the crankarm of the second member.
 3. Mechanical means for automatically adjusting headlamps of a wheeled vehicle according to claim 1 including a first member comprising a bellcrank lever suspended movably from the body and of which one arm engages a rear wheel axle and differential casing of the vehicle and another arm providing connection for one end of the cable whereas the second member comprises an anti-roll bar having a crankarm on a center portion, a movable head on the opposite end of the cable disposed in spaced relationship forwardly of a crankarm of the oscillatable shaft and the crankarm of the anti-roll bar which is disposed rearwardly of the crankarm of the oscillatable shaft, compression springs bearing on front and rear sides of the crankarm of the oscillatable shaft and the head and crankarm of the anti-roll bar.
 4. Mechanical means for automatically adjusting headlamps pivotally mounted on a resiliently suspended body of a vehicle having wheels at front and rear ends for maintaining a substantially constant angle between light beams emmited by the headlamps and a mean plane containing the axes of the front and rear wheels of the vehicle on uneven sagging of the front and rear ends of the body relative to said plane, including; a journalled oscillatable shaft transversely across the body and having crankarms connected by links to the headlamps, to a spring providing a bias to tilt the headlamps in one direction, and to an actuating cable; a lever suspended from the body and having an arm portion engaging a central portion of a rear wheel axle and differential gear casing and another arm providing a connection for a flexible cable; a transverse bar connected by one end pivotally and by an opposite end pivotally and slidably to spring support and wheel mounting pivoted beams of the vehicle; a cable pulley journalled on the center portion of the bar; a flexible actuating cable connected by one end to said lever and by the opposite end to a crankarm of the oscillatable shafts whereas an inTermediate portion is passed around the pulley whereby sagging of the rear end of the body cause downward tilting of the headlamps against the biasing action of the spring while sagging of the front of the body cause raising of the pulley and tilting of the headlamps in the opposite direction by the spring, the movement of the pulley being adapted to counteract the action of the lever for tilting movement of the headlamps proportionately to the vertical movements of the rear and the front ends of the body relative to said plane.
 5. Mechanical means for automatically adjusting headlamps pivotally mounted on a resiliently suspended body of a vehicle having wheels at a front end and at a rear end for maintaining a substantially constant angle between light beams emitted by the headlamps and a mean plane containing the axes of the front and the rear wheels of the vehicle on uneven sagging of the front and rear ends of the body relative to said plane including a journalled oscillatable shaft transversely across the body and having crankarms connected by links to the headlamps, to a spring providing a bias to tiltable headlamps in one direction, and to an actuating cable; a transverse bar swivelably attached to short downwardly directed levers on tying members extending pivotally from the vehicle body to bearing mountings of the rear wheels and a connection on a center portion of the bar for one end of an actuating cable; a transverse bar connected by one end pivotally and by an opposite end pivotally and slidable to spring supporting and wheel mounting pivot beams of the vehicle, a pulley rotatable on a center portion of the bar and engaged by an intermediate portion of the cable which is connected to a crankarm of the oscillatable shaft whereby on sagging of the rear of the body of headlamps are tilted downwardly against the biasing action of the spring while sagging of the front of the body causes raising of the pulley for upward tilting of the headlamps, said raising of the pulley being adapted to counteract the action of the cable from the rear of the vehicle for tilting of the headlamps proportionately to the uneven vertical displacement of the front and rear ends of the body relative to said plane.
 6. Mechanical means for automatically adjusting headlamps of a vehicle according to claim 5 wherein the bar at the rear of the vehicle is provided with a rotatable pulley substantially at a center portion thereof whereas the actuating cable has a rear end connected to the body of the vehicle and is passed over the pulley of the bar at the rear of the vehicle and over the pulley on the bar at the front of the vehicle for connection with an opposite end to a crankarm of the oscillatable shaft.
 7. Mechanical means for automatically adjusting headlamps pivotally mounted on a resiliently suspended body of a vehicle having wheels at a front end and at a rear end for maintaining a substantially constant angle between light beams emitted by the headlamps and a mean plane containing the axes of the front and the rear wheels of the vehicle on uneven sagging and rear end of the body relative to said plane, including: a journalled oscillatable shaft transversely across the body and having crankarms connected by links to the headlamps to a spring providing a bias to tilt the headlamps in one direction, and to an actuating cable; a first member at the rear of the vehicle and attached to the body and mountings for the rear wheels for movement in proportion to vertical movement of the body relative to the wheels; a second member at the front of the vehicle attached to the body for movement in proportion to vertical movement of the body relative to the front wheels; a lever having one end connected by a cable to a crankarm of the first member, an opposite end connected by a cable to a crankarm of the oscillatable shaft, a center portion connected by a cable to a crankarm of the second member, a portion between the connections of the first and second member connected to the body by a spring; wheReby on uneven sagging of the rear and front ends of the body the end of the lever connected to the crankarm of oscillatable shaft is swung to an extend proportionately to the said uneven downward movement of the body causing similar proportional tilting movement of the headlamps relative to the plane.
 8. Mechanical means for automatically adjusting headlamps as claimed in claim 7 wherein the front and rear members comprise anti-roll bars having on center portions crankarms which are attached by the cables to the levers at the said positions, the proportions of the lengths of the crankarms relative to the spaced positions of connection of the respective cables to the lever from the position of attachment of the lever to the crankarm of the oscillatable shaft being the same.
 9. Mechanical means for automatically adjusting headlamps as claimed in claim 7 wherein the first member comprises a crankarm on each of two rear wheel mounting levers, pivotally connected to the body, whereas the cable provides a pair of diverging end portions of which the ends are each connected to one or said crankarms.
 10. Mechanical means for automatically adjusting headlamps as claimed in claim 7 wherein a substantially transverse lever is provided having an intermediate portion connected to the crankarm of the oscillatable shaft and having opposite ends connected to crankarms of anti-roll bars by cables, the proportion of the lengths of the crankarms relative to the distance of attachment of the respective cables to the lever from the position of connection of the lever to the crankarm of the oscillatable shaft being the same. 